Benn was the last Labour MP to speak in a heated debate that lasted more than 10 hours and included more than 100 statements from backbench MPs.

In a rousing speech that prompted MPs from all political parties to break with convention and burst into cheering, applause and standing ovations, Benn made the case for supporting military action in Syria.

Benn told MPs that Isis are “fascists, not just their calculated brutality, but their belief that they are superior to every single one of us in this chamber tonight and all of the people we represent”.

“They hold us in contempt,” he said. “They hold our values in contempt. They hold our belief in tolerance and decency in contempt. They hold our democracy – the means by which we will make our decision tonight – in contempt.

“And what we know about fascists is that they need to be defeated and it is why, as we have heard tonight, socialists and trade unionists were just one part of the international brigade in the 1930s to fight against Franco.

"It’s why this entire House stood up against Hitler and Mussolini. It’s why our party has always stood up against the denial of human rights and for justice and my view, Mr Speaker, is that we must now confront this evil. It is now time for us to do our bit in Syria.”